The invention relates to a device for transferring printed products out of the transport channel of a gathering and collating machine in which the printed products are moved along in a timed flow.
Transfer out devices of the aforementioned type have been known for a long time. They are used to transfer printed products that are defective or used for control purposes out of the transport channel and, in particular, to pull stacks or individual sheets from the timed flow without interrupting the production. With this type of transfer out device, the printed products are generally transferred out of the transport channel either perpendicular to the printed product in an upward direction, or parallel to the surface of the printed product toward the side, or at a slant in an upward direction. The change in direction during the transfer out is guided either by flaps that can be activated or by gripping elements that act in a perpendicular direction upon side areas of the printed products.
A transfer out device of this type is disclosed, for example, in reference DE 37 21 391 A. This transfer out device comprises a clamping system consisting of front and a rear clamping devices provided with clamping grippers that act jointly in pairs under the force of a spring element. The printed products to be transferred out are gripped with these clamping grippers.
A transfer out device is also known from reference CH 657 598 A, the transfer out device being provided with a conveyor, arranged at an angle to the transport channel, for transferring out the printed products. The conveyor has an endlessly circulating chain, which is held at both ends by chain wheels and forms a component of a branch conveyor. A plurality of branch-off pins that can be pivoted between a pulled back position and an extended position are arranged on the endless chain. In the extended position, the branch-off pins grip defective stacks to remove them from the transport channel.
With the transfer out device according to reference DE 37 21 391 A, it is possible per se to separate out defective printed products, and in particular stacks of printed products, without interrupting the operation of the gathering and collating machine. Since the thicknesses of the printed products, generally stacks of several printed sheets, can vary considerably, the transfer out device must be designed such that it can adapt to the thickness of the printed products to be transferred out, thus requiring a relatively expensive and involved design.